Three Chinese vessels have reportedly been hijacked off the coast of northeastern China by unidentified North Koreans.

Twenty-nine fishermen were in the separate vessels when a group of armed men boarded their boats and took over in the waters between China and North Korea. The hijackers are demanding a ransom of 1.2 million yuan ($190,000).

The North Koreans gave a phone to the kidnapped boat owner in order for him to contact his fellow sailors, asking for a ransom of 400,000 yuan per boat.

Sun, a fellow sailor who has been keeping in touch with the hostages said he could hear sailors being beaten and crying in the background. The hostages haven’t eaten for two days. The foreign ministry are “keeping close contact with North Korea to safeguard our citizens’ rights and interests”, said reports.

Sun says he is “100 percent sure” that some of the hijackers are Chinese. Chinese fishermen are often caught fishing in waters that are claimed by both China and neighboring countries. Reports did not indicate whether the hijackers are security forces from North Korea.